Greetings,I'm about to tackle this same problem myself, since I'm about to ditch a pair of Solaris boxes for my NFS mounted mail spools and instead move to filers. My plan is to instead use Linux HA to have two machines as a failover cluster mounting the database via NFS. I think this'll be a lot cleaner, and will also integrate in a nicer fashion with the concept vpopmail has of mysql replication.
I've got a working mysql and vpopmail setup going, with replication support. For those that don't know, replication support in vpopmail means that all updates go to a single server, where lookups can be sent to another server. I have a local copy of the replicated database on each machine to spread the load out and to be more robust in the face of other machine failure. Unfortunately, this makes each machine dependant on the mysql update server, since each login triggers an update to the lastauth table. How have other people solved this, without just disabling mysql logging? Has anyone used any of the more rare multiple-master ring topologys in mysql to let each server update?
I really don't want to setup a dedicated "mysql server" just to handle updates like this. I'm also planning to start using spamassassin mysql preferences, so I'd like any server to be able to update the database with user preferences, and the change replicate around. Does anyone have any input on this? Anyone use squirrelmail with their preferences in the database as well?
Your other option, if you've got money to spend on the problem, is to get a database server which is both supported by vpopmail and supports more flexible replication. I'd recommend Sybase, since they support real two way replication, and their replication speed is amazing.
Hope that helps,
Webley Systems, Inc.